On 8 December 1978, two weeks shy of my 14th birthday, I experienced my first gig: Muddy Waters, at the Rainbow theatre in London (if you discount the Wombles at South Hill Park in Bracknell, a few years earlier). The man born McKinley Morganfield, in Rolling Fork, Mississippi, who would have celebrated his 100th birthday on 4 April – the king of the electric blues, with his red telecaster, cream suit, pencil moustache, and Cheshire cat grin – was the first musician to get my mojo working.

He hardly moved on stage, just perched on a stool, removed his jacket, smiled mischievously, then closed his heavy-lidded eyes and drifted off into some deep blues reverie – all the whileplaying the rawest riffs known to humanity. It was loud, that sound, deep, warm, and soulful – even for a first gig, I knew this was perfection. It hit you just in the right place, a vast, generous wash of instruments, played by men from Chicago by way of the deep south, with Muddy Waters’ mesmeric voice sailing on across the top, regaling us with tales of voodoo, king bees buzzing around hives, and doing well with ladies. From him, none of it sounded boastful.

I knew the songs already, having been a Manish Boy since the age of nine, and I was, by now, beginning to work out what the Hoochie Coochie Man was all about.

Perhaps I should explain how I came to the blues so young, and who it was that brought me to them. My devil-at-the-crossroads moment came during the double general election year of 1974, when my father, the agent for the Wokingham Liberal party, introduced me to a tall, slim man in a great suit, smoking a cigarette in the exact way I felt a cigarette should be smoked, who had come to volunteer his services in unseating the Tories. He looked like a cross between Keith Richards and Rodney Bewes, and his name was Peter Banham.

He’d come to our house to discuss election strategies with Dad, over whisky and sodas – I don’t think they ever formed any, and the Liberal party had enough problems on its own without their help, but these evenings were wonderful.

A couple of weeks into guitar lessons with a lovely schoolteacher called Jill, who had written a song for Rags the Blue Peter Horse that was broadcast on BBC1, I was able to play Oh Where Oh Where Has My Little Dog Gone?, a sad lament to a lost pooch. As I strummed it for Peter, hopefully, I felt sure it would earn his approval. It didn’t. He was polite enough, of course, but as my parents beamed with pride at their six-string wunderkind, he asked if this was really the kind of thing I wanted to play.

Come to think of it, no, I replied. Then the suburban epiphany began, and the devil’s music came to Wokingham. The man in the sharp suit, with the cigarette glowing in the side of his mouth, picked up my guitar and began to play.

“Gypsy woman told my mother, before I was bornYou got a boy child comin’ gonna be a son of a gun.”

The words, and sheer brutality of the riff, almost broke me in two.

And that’s when it started, year zero: from teenybopper to bluesman in one evening. As far as I was concerned, the little dog could stay lost, all I wanted was a John the Conqueroo, and a black cat bone – which, with our own midnight black, ancient moggy, was a distinct possibility.

Peter brought me several boxes of records to keep safe, away from the curious hands of his two small daughters, and perfect for mine. They contained everything the youthful bluesman could ever want. Muddy Waters, Bo Diddley, Howlin’ Wolf, Big Bill Broonzy, Lightnin’ Hopkins. Most still carried the label of Dobell’s Jazz Shop on Charing Cross Road, the mecca of the early 60s British blues explosion. Had it been 10 years earlier, I could have formed the Rolling Stones myself. I practised after school each afternoon, imagining the vast Mississippi, rather than the Thames Valley. Then came Tony Palmer’s All You Need Is Love music documentaries. With no YouTube, this one glimpse of Muddy Waters had to last years. Not only did he look like the cat who got the cream, he had a great pompadour going on. Even his speaking voice was dark and sensual, with a hint of danger.

Hearing a 12-year-old boy with a chorister voice, growling that He’d Just Like To Make Love To You, was enough to make our next-door neighbour Joan cry with laughter. I went electric soon after this, and she wasn’t laughing then – and I got called much worse than Judas.

My love of Muddy Waters has stood me in good stead. At secondary school, it earned me the protection of the school psychopath. He’d learned that a boy in the first year had been blowing a blues harp on Winnersh station as the downhome train came in. He loved Chicago blues, and until he was expelled for arson, I was untouchable.

So back to the Rainbow, 8 December 1978, and, of course, it’s Peter who has brought me here. We’re at the front of the balcony, and – in Muddy’s own words – “I’m ready, as ready as anybody can be”. I am watching the past, the present, and my future.

Peter died very suddenly, just as I was about to make my first solo record in 1989. I put Hoochie Coochie Man on the flip side.

Today, as I play the 1958 Best of Muddy Waters LP, he gave me, each crackle is still a part of me. A fleck of paint on its opening groove creates a slow heartbeat, just before Hoochie Coochie Man kicks in, as if the record is actually alive. It is, and so is Peter.

These days, I do have a John the Conqueroo, acquired from New Orleans, and my mojo, although lost several times, appears to be working – but I never got a black cat bone. Happy 100th birthday, Muddy Waters!

John Moore’s ticket to see Muddy Waters in 1978 – his first ever gig. Photograph: John Moore